Evaluation of ammonia fibre expansion (AFEX) pretreatment for enzymatic hydrolysis of switchgrass harvested in different seasons and locations

Table 3 Optimal enzyme loadings for enzymatic hydrolysis of four harvests of switchgrass.

	CIR: July	CIR: October	Alamo: July	Alamo: October
Accelerase^a	5.0	6.4	5.0	5.0
Novozyme^a	0	0	0	0
Monomer xylanase^a	5.0	3.6	5.0	5.0
Monomer pectinase^a	5.0	5.0	5.0	5.0
Predicted sugars^b	523	411	409	557
Actual sugars^c	521	410	410	445
Sugar yield (%)	89.0%	60.9%	64.0%	68.9%
Glucose yield^c	321	223	210	237
Xylose yield^c	200	187	201	208
R²	81.3%	76.5%	81.5%	64.9%

^aAll values are in mg enzyme per g dry switchgrass; ^bmonomeric sugars released (g/kg switchgrass) after 72 h of hydrolysis as predicted by the model; ^cactual monomeric sugars released (g/kg switchgrass) after 72 h of hydrolysis.
CIR = Cave-in-Rock.